Crystal structure of the cytotoxic macrocyclic trichothecene Isororidin A

The absolute configuration of Isororidin A, isolated from the fungus Myrothesium verrucaria, has been determined by X-ray crystallography.


Special details
Geometry.All esds (except the esd in the dihedral angle between two l.s.planes) are estimated using the full covariance matrix.The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry.An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s.
planes.Supporting information, sup-10   to 39 % in 2 min (flow rate 0.2 mL min -1 ), and then to 99.9 % (flow rate 0.4 mL min -1 ) in the following 11 min.Then it kept constant for 2 min (flow rate 0.48 mL min -1 ), then initial conditions were restored within 0.1 min, kept for 3 min and then the flow rate decreased to 0.2 mL min -1 .The injection volume was set up to 5 μL.
After a series of open-column chromatographic separations, the final semi-preparative HPLC purification was performed on a C18 column (250mm × 10mm × 5μm, Dr. Maisch GmbH, Germany), using a linear gradient elution scheme of MeOH/deionized water.HPLC system consisted of an source: micro-focus sealed X-ray tube Absorption correction: analytical CrysAlis PRO 1.171.40.67a (Rigaku Oxford Diffraction, 2019) Analytical numeric absorption correction using a multifaceted crystal model based on expressions derived by R.C. Clark & J.S. Reid.(Clark, R. C. & Reid, J. S. (1995).Acta Cryst.A51, 887-897) Empirical absorption correction Acta Cryst.(2024).C80, https://doi.org/10.1107Allesds (except the esd in the dihedral angle between two l.s.planes) are estimated using the full covariance matrix.The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry.An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s.planes.

All
1D and 2D spectra were obtained using the standard Bruker software.Residual solvent signals were used as internal standards (reference signal) CHCl 3 (δH 7.26 ppm and δc 77.0) and CHD 2 OD (δH 3.31 ppm and δC 49.0 ppm).The observed chemical shift (δ) values were given in ppm and the coupling constants (J) in Hz.

Table S1 :
Experimental details of Isororidin A crystal data collected at 293 K

Table S2 :
Experimental details of Isororidin A crystal data collected at 100 K

Table S3 :
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 ) for

Table S8 :
Carbon atoms numbering followed in the Roridin A structure deposited by Jarvis et al.
For positive ionization mode, the mobile phases were water/methanol 90/10 (solvent A) and methanol (solvent B) both amended with 5mM ammonium formate and 0.01% formic acid.The adopted gradient elution program started with 1% B with a flow rate of 0.2 mL min -1 for 1 min and it increased ECOM, Prague, Czech Rep.).NMR spectra were recorded at 298º K on a Bruker Avance III 600 spectrometer (600.23 MHz for 1 H, 150.93 MHz for 13 C) equipped with a PABBI inverse detection probe with a z-axis gradient coil and a B-ACS 60 autosampler and on a Bruker DRX 400 spectrometer (400.13MHz for 1 H, 100.61MHz for 13 C) equipped with a PABBI inverse detection probe with a z-axis gradient coil.